This is a five-year training and research proposal to develop a food frequency questionnaire (FFQ) to measure dietary intake and to validate the newly developed FFQ among the African American population in Washington DC (D.C.). At present there is no specific instrument designed to measure dietary intake in African Americans. The study's objectives are: 1) to collect contemporary detailed dietary data from low and middle SES groups; 2) to develop an ethnically-oriented dietary assessment instrument (FFQ) for the African American population; 3) to validate the new FFQ utilizing the same population; and 4) to compare the newly developed FFQ with other instruments commonly used. To develop the FFQ, 600 African American subjects will be selected: 300 subjects will be from D.C. public housing communities (low SES group), and tile other 300 will be employees of local medical institutions. Dietary information will be collected through multiple 24-hour recalls. An ethnically-specific FFQ will be developed utilizing 24-hour recalls. To validate the newly developed FFQ, 336 new subjects will be selected: 168 subjects will be from public housing communities, and the other 168 will be employees of the medical institutions. Initially, the newly developed FFQ will be administered to all subjects. Next, three 24-hour recalls will be collected from each of the subjects, and compared to the results of the FFQ. Finally, a comparison with other instruments commonly used will be performed. The previously developed FFQs of both Willett and Block will be administered to the same 336 subjects. Comparisons will be made between the results from the newly developed FFQ and the other two commonly used FFQs. The newly developed FFQ should facilitate research on the relationship between nutrition and cancer.